Code. Books. Outdoors.

Recommendations wanted: solar charger

I’ve been looking a bit at solar chargers as a gift recommendation for Christmas. I have yet to find the ideal one, so I thought I’d ask for input. Here are the specifications that I would like to see:

Has internal, user-replaceable battery for storing power

Indicator of current charge level and solar “strength” level

Can charge internal battery from USB or sun, I already have a combo 12VDC/120VAC to USB adapter that would be an ideal partner for this feature

Has place to charge 2 AA or AAA batteries (note that a clever design could make these the internal battery)

Has either a clip or lanyard hole to fasten to backpack

Reasonable size/weight, probaby in the 1/2 pound range (minus batteries being charged) and in the “deck of playing cards” size range (which implies that the panels are foldable, I think the Solio design is nice for that)